Compared with low molecular weight PEGs (such as PEG-200 to PEG-600) and high molecular weight PEGs (such as PEG-4000 to PEG-20000), polyethylene glycol PEG-2000's most core advantage lies in its precise balance of molecular weight and physical properties. According to the Guoli Chemical product database, the molecular weight range of PEG-2000 is 1800~2200, melting point is approximately 45~55°C, and it is a white waxy solid at room temperature. This characteristic makes it significantly superior in processing convenience compared to liquid low molecular weight PEGs—it can be used as a solid carrier (e.g., suppository base, pill matrix), while its melting temperature is much lower than that of PEG-4000/6000 (melting point approx. 55~65°C), resulting in lower energy consumption, safer operation during melt processing, and reduced risk of degradation for heat-sensitive drugs.
Secondly, the HLB value of PEG-2000 is as high as 20, making it a completely hydrophilic nonionic surfactant, with excellent solubility in water and good compatibility with anionic, cationic, and other nonionic substances. Compared to higher molecular weight PEG products, the aqueous solution viscosity of PEG-2000 is moderate (kinematic viscosity at 100°C is 50~65 mm²/s), avoiding operational difficulties or decreased system fluidity caused by excessive viscosity. Its hydroxyl value is 51~62 mg KOH/g, and the content of terminal active hydroxyl groups is sufficient. It exhibits excellent reactivity and product yield as an intermediate for esterification/etherification reactions, making it an ideal precursor for preparing a series of nonionic surfactants such as polyethylene glycol fatty acid esters and polyethers.
Thirdly, PEG-2000 exhibits outstanding safety performance. Guoli Chemical's test data show that its heavy metal content is ≤5 mg/kg and arsenic content is ≤2 mg/kg, meeting stringent pharmaceutical-grade requirements. The actual oral LD₅₀ value in rats is typically >5000 mg/kg, with no skin irritation, no eye irritation, and no sensitization, classifying it as a low-toxicity substance. Compared with certain low molecular weight PEGs (e.g., PEG-200/300) that may have mild mucosal irritation, PEG-2000 has a safety advantage, which is a key reason for its widespread use in pharmaceutical preparations such as suppositories, ointments, and pills.
| Parameter Item | Guoli Chemical PEG-2000 Indicator | Advantages Compared to Similar Products |
|---|---|---|
| Molecular Weight | 1800~2200 | Moderate molecular weight, balancing solubility and solid form |
| Melting Point | 45~55°C | Lower than PEG-4000/6000 (55~65°C), easier melt processing |
| HLB Value | 20 | Completely hydrophilic, excellent emulsification and dispersion capability |
| Hydroxyl Value | 51~62 mg KOH/g | Sufficient terminal hydroxyl activity, high efficiency in derivatization reactions |
| Acid Value | ≤0.5 mg KOH/g | Low acid value ensures formulation stability and reduces side reactions |
| Kinematic Viscosity (100°C) | 50~65 mm²/s | Moderate melt viscosity, better operational convenience than high molecular weight PEG |
| Effective Content | ≥99% | High purity, minimal impurity interference |
| Heavy Metals | ≤5 mg/kg | Meets stringent pharmaceutical-grade standards |
| Flash Point | >240°C | High flash point, good processing safety |
| Chemical Stability | Resistant to acid, alkali, and hard water | Stable over a wide pH range and under different water quality conditions |
Pharmaceutical field is the application direction where PEG-2000's advantages are most prominent. Its melting point range of 45~55°C precisely matches the transition interval between body temperature (37°C) and room temperature. As a suppository base, it enables rapid melting and drug release at body temperature; as a pill matrix, the solid dispersion formed after melt cooling can significantly improve the dissolution rate of poorly soluble drugs. The recommended dosage depends on the specific prescription process, generally 60%~90% of PEG-2000 in suppositories.
Cosmetic field, PEG-2000 is particularly suitable for medium to high-end creams and serums due to its excellent moisturizing and water-locking ability and non-sticky texture. Recommended addition amount is 1%~5%. Industrial field, as a smoothing agent and bundling agent in textile spinning oils, and as a lubricity-enhancing component in metalworking fluids, PEG-2000's low thermal decomposition residue (superior to low molecular weight PEG) and moderate viscosity make it the best overall performance choice.